The present invention generally relates to the field of microelectromechanical (MEM) systems and, more particularly, to a microelectromechanical system which includes a suspension assembly for at least assisting in supporting a movable element (such as an electrostatic comb).
Microelectromechanical (MEM) technology generally involves the fabrication of small mechanical devices on a substrate (usually silicon). The various microstructures of a MEM system may be formed using a variety of appropriate processes. An example of such a process is a surface micromachining process that generally entails depositing alternate layers of structural material and sacrificial material on an appropriate substrate, which generally functions as a foundation for the resulting microstructure(s). Various patterning operations may be executed on one or more of these layers (usually, but not always, before the next layer is deposited) so as to define the desired microstructure(s). Generally, after at least a portion of the microstructure(s) has been defined in an appropriate manner, such as by the process described above, the various sacrificial layers (if such layers are present) may be removed by exposing the microstructure(s) and/or the various sacrificial layers to at least one etchant to xe2x80x9creleasexe2x80x9d the resulting microstructure(s).
MEM-based systems can generally include suspension assembly microstructures that support movable elements, such as electrostatic elements of electrostatic actuators. These electrostatic actuators may have, for example, both stationary and moveable electrostatic combs, which, in combination, may function to provide power motive sources to microstructure(s) of microelectromechanical systems. In the case of a suspension assembly being utilized in an electrostatic comb actuator application, one or more moveable combs of the electrostatic comb actuator(s) generally may be attached to the suspension assembly to enable each moveable comb to move toward and/or away from its accompanying stationary comb.
However, various problems have been associated with conventional suspension assemblies. Take, for example, the case of a moveable element such as a moveable electrostatic comb associated with a conventional suspension assembly. Generally, each electrostatic comb has a base beam with a plurality of comb fingers extending therefrom. An increasing amount of voltage is typically needed to urge a moveable comb (via movement of the suspension assembly) toward a corresponding stationary comb to produce a resultant actuation (e.g., movement of a mirror in an optical switch application). More specifically, the application of voltage to, for example, the stationary comb of the actuator creates a variety of attractive forces between the moveable and stationary combs. A first of such attractive forces is a xe2x80x9ccomb forcexe2x80x9d generally defined by the change in capacitance per unit of displacement that arises between each side of each movable comb finger and sides of the stationary fingers by which it passes. Typically this attractive comb force will generally vary with respect to the square of the applied voltage. This comb force also is generally the main force that affects the positioning of the moveable comb with respect to each corresponding stationary comb in electrostatic actuator assemblies.
A second of such attractive forces is a xe2x80x9cparallel plate forcexe2x80x9d generally defined by the attraction of each finger of the moveable comb toward adjacent stationary comb fingers disposed on each side of the moveable comb fingers. Since this parallel plate force is generally oriented in direction that is substantially perpendicular to the movement of the moveable comb, and since the stationary comb elements are typically equidistantly spaced from each corresponding moveable comb finger, the parallel plate force is generally offset and can (for the most part) be ignored.
A third of such attractive forces is a variation of the parallel plate force referred to as a xe2x80x9cparasitic tip forcexe2x80x9d. This parasitic tip force generally refers to the attraction of each free end of each moveable comb finger toward the base beam of the stationary comb (and/or the attraction of each free end of each stationary comb finger for the base beam of the moveable comb). Accordingly, the parasitic tip force is generally oriented in direction that is substantially parallel to the movement of the moveable comb. This parasitic tip force generally is insignificant to the function of the electrostatic comb actuator until the free ends of the moveable comb fingers reach (or surpass) some minimum threshold distance of separation with respect to the base beam of the corresponding stationary comb.
Even though the attractive forces of an electrostatic actuator are generally opposed by an attached suspension assembly (typically providing some sort of restorative force), the parasitic tip force, in combination with the comb force, tends to overcome restorative forces of conventional suspension assemblies. In other words, as the free ends of the moveable comb fingers tend reach or surpass this minimum threshold distance of separation from the base beam of the stationary comb, this parasitic tip force causes an increase in the attractive forces of the stationary comb. It can be said then that the total attractive force of the stationary comb increases in a substantially nonlinear fashion at least when the free ends of the moveable comb fingers reach or surpass the minimum threshold distance.
As a result, conventional suspension assemblies have allowed their attached moveable combs to remain locked into an interdigitated engagement with the corresponding stationary comb, thus rendering the electrostatic actuator at least temporarily inoperable. While conventional electrostatic actuators have traditionally relied on a reduction in the voltage applied to the stationary comb and/or the restorative spring force of the accompanying suspension assembly to provide a restoring force to draw the moveable comb(s) back out of (or at least to a lesser degree) interdigitation with the stationary comb(s), the designs of conventional suspension assemblies have not been able to successfully address the occurrence of runaway conditions and associated adhesion/stiction between the fingers of the stationary and moveable combs (or other opposing elements of a MEM system). In other words, once a moveable comb has been urged toward a corresponding stationary comb (generally via voltage applied to the stationary comb), the moveable comb may xe2x80x9csnapxe2x80x9d into and maintain, at least momentarily, an interdigitated actuation relationship with the stationary comb even after the applied voltage has been reduced. Stated another way, the designs/configurations of conventional suspension assemblies have not been successful at combating the additional parasitic force to avoid runaway conditions or, where such conditions have occurred, to overcome the tendency for corresponding moveable and stationary combs to stay xe2x80x9cstuckxe2x80x9d together until the applied voltage has been reduced below some threshold value. Several attempts have been made to combat this problem. For example, some attempts have included varying the length and/or thickness of spring arms associated with the suspension assembly, however such attempts have generally proven unsuccessful.
An additional consideration is that the xe2x80x9cspacexe2x80x9d (or xe2x80x9creal estatexe2x80x9d) on a base substrate to which a MEM system is formed is generally limited. Accordingly, MEM systems are continually being designed to reduce the space occupied by electrostatic actuators. A significant amount of the designs include moving the combs elements of the actuator assemblies closer together, requiring even greater control of the comb elements. Accordingly, it would be desirable to provide a suspension assembly that is capable of addressing both the comb forces and parasitic forces associated with electrostatic comb actuators.
Accordingly, the present invention is generally directed to microelectromechanical (MEM) systems. More specifically, the present invention relates to a suspension assembly for supporting an actuation apparatus (e.g. a movable electrostatic comb) of a microelectromechanical system. The suspension assembly of the present invention desirably addresses the lack of electrostatic element control associated with conventional suspension assemblies. While particularly desirable applications of this suspension assembly may be in microelectromechanical (MEM) systems (e.g., optical switches), the suspension assembly of the present invention may be utilized in any appropriate application for which enhanced control of a microstructure is desired/required.
A first aspect of the present invention relates to a method and system involving a suspension that provides a restoring force (e.g., to resist the attractive force between converging comb elements and/or pull an attached moveable comb element away from a corresponding stationary comb) having a non-linear characteristic. Thus, this first aspect at least assists in controlled movement of a first moveable element of a microelectromechanical system relative to a base substrate. The system generally includes a moveable element supported at least in part by a suspension. The moveable element is moveable across a range of displacement. The suspension assembly exerts a restorative force that varies as a nonlinear function of displacement within the displacement range. In one embodiment, the system includes a moveable beam having first and second lateral sides, and at least one suspension arm extending laterally out from the beam. For example, multiple suspension arms may extend from the first and second lateral sides of the beam.
Various refinements exist of the features noted in relation to the first aspect of the present invention. Further features may also be incorporated in this first aspect as well. In addition, various features discussed herein in relation to one or more of the other aspects of the present invention may be incorporated into this or any other aspect of the present invention as well, and in the manner noted herein.
A second aspect of the present invention relates to a method and system involving a suspension assembly that includes at least one arm having a nominal length (in a resting position) and a stretched length (in a stretched position) longer than the nominal length of the arm. The system generally includes a moveable member and one stretchable arm interconnected to the moveable member. The arm may be anchored to a substrate or otherwise constrained so as to stretch in response to or otherwise in connection with movement of the moveable member. In one embodiment, the system includes a moveable center member having first and second lateral sides, and one or more of each of first and second arms extending laterally out from the center beam. Generally, the first arms extend from the first lateral side of the center beam, and the second arms extend out from the second lateral side of the center beam. Preferably, the first and second arms exert substantially counteracting lateral forces on the center member. Each of the first and second arms has a nominal length, and when the center member of the system is in a displaced position, each of the first and second arms has a stretched length. As the terms tend to indicate, the stretched length is generally longer than the resting length of the corresponding first and second arms.
Various refinements exist of the features noted in relation to the second aspect of the present invention. Further features may also be incorporated in this second aspect as well. These refinements and additional features may exist individually or in any combination. For example, the longitudinal center member can include first and second elements that are joined together. In other words, the first and second elements may be interconnected to function as a single, solitary beam unit. One way of accomplishing this include a homogenous interface that results during the fabrication process of the suspension assembly. However, other ways (e.g., welding or clamping) of joining two beams together to function as a single beam structure may be appropriate.
The first and second arms can be substantially perpendicular to the center member when the center member is in a resting position. A xe2x80x9cresting positionxe2x80x9d generally refers to the condition of the center beam when substantially no actuation forces (e.g., electrostatic static forces) are acting upon the member. In other words, the resting position generally reflects a positioning which effectively indicates a substantial freeness from biasing force(s).
A third aspect of the present invention relates to a method and system involving a suspension assembly that provides a restoring force defined at least in part by one or more arms of the suspension assembly being bent/flexed to provide a spring force and one or more arms of the suspension assembly (the same or different than the bent/flexed arms) being stretched to provide a tensile force. This third aspect at least generally assists in controlled movement of a first moveable member of the system relative to a base substrate. The system of this third aspect generally includes a first moveable beam and one or more first suspension arms. When the first moveable beam is moved, one of the suspension arms is at least stretched, and one of the suspension arms is at least flexed.
Various refinements exist of the features noted in relation to the third aspect of the present invention. Further features may also be incorporated in this third aspect as well. These refinements and additional features may exist individually or in any combination. For example, one or more of the suspension arms may be anchored to the base substrate. Additionally or alternatively, one or more of the suspension arms may be free of restrictive connections to the base substrate. In one embodiment, some suspension arms are anchored and others are not. In any event, either or both of the anchored and unanchored arms may stretch, and either or both may flex.
A fourth aspect of the present invention relates to a method and system involving supporting a first structure of a system by providing a suspension restoring force as resistance to an attractive electrostatic force. The restoring force is preferably directed opposite the actuation force and, more preferably, increases/decreases generally proportionately to the actuation force, in each case, as a function of displacement. The system generally includes a base substrate, an actuation structure, and a first suspension structure. The actuation structure is generally interconnected with a first actuator element of the microelectromechanical system. The first suspension structure generally allows for movement of the actuation structure across a range of positions relative to the base substrate in response to a corresponding range of actuation forces applied to the actuation structure. This range of positions is generally defined by a first position corresponding to a first actuation force value of zero or greater and a second position corresponding to a second actuation force greater than the first actuation force. The first linkage structure provides a nonlinear resistance force against the actuation force such that the resistance force varies in a nonlinear fashion with respect to positions within the range of positions.
Various refinements exist of the features noted in relation to the fourth aspect of the present invention. Further features may also be incorporated in this fourth aspect as well. These refinements and additional features may exist individually or in any combination. For example, the first position may include the first actuator element being dissociated (i.e., separated by a first distance) from a second actuator element.
A fifth aspect of the present invention is embodied in a suspension assembly formed on a base substrate and having a support structure, and an intermediate actuation structure. The support structure is generally interconnected with the base substrate and generally includes a medial support rail and a plurality of support beams extending out from first and second lateral sides of the medial support rail. The intermediate actuation structure is generally interconnected with the support structure and disposed between the support structure of the suspension assembly and the base substrate of the microelectromechanical system. The suspension assembly of this fifth aspect also generally includes a first linkage structure operatively interposed between the base substrate and the support structure. In addition, the suspension assembly also has a second linkage structure operatively interposed between the support structure and the intermediate actuation structure.
Various refinements exist of the features noted in relation to the fifth aspect of the present invention. Further features may also be incorporated in this fifth aspect as well. These refinements and additional features may exist individually or in any combination. For example, the actuator element is preferably interconnected to the intermediate actuation structure; however, other locations of the actuator element may be appropriate. The actuator element may be connected to the intermediate actuation structure in such a manner that the actuator element and the support structure are substantially coplanar. This actuator element can be a variety of appropriate microstructure devices including, but not limited to, an electrostatic comb.
The support structure in the case of this fifth aspect may include a medial support rail and a plurality of support beams extending out from the medial support rail. In such variations, the support beams may have distal ends remotely disposed from the medial support rail, and connected to the base substrate (which may include a voltage reference plane of sorts) via linkages of the first linkage structure. This first linkage structure may generally enable at least part of the support structure to move relative to the base substrate. Similarly, the second linkage structure may generally enable at least part of the intermediate actuation structure to move relative to at least one of the support structure and the base substrate. In some variations of this fifth aspect, the first and/or second linkage structures may exhibit a resilience (i.e., have some detectable elasticity, while other variations may include one or both the first and second linkage structures being substantially rigid (i.e., being devoid of any detectable amount of elasticity. One or both of these first and second linkage structures may be made up of at least one layer of polysilicon. In some variations, the first linkage structure may be made up of at least three layers of polysilicon.
In the case of this fifth aspect, the actuation beams of the support structure may have peripheral ends remotely disposed from the central actuation rail and connected to the support structure via the second linkage structure. In some variations, the intermediate actuation structure only interconnects with the base substrate via the support structure. In other words, the intermediate actuation structure generally is designed/configured to avoid direct contact with the base substrate. The intermediate actuation structure may be suspended over the base substrate due to the second linkage structure connecting the intermediate actuation structure to the support structure. If the intermediate actuation structure is displaced by a first distance, the support structure can generally be displaced by a second distance less than the first distance. The intermediate actuation structure may have at least one linkage channel. That is, at least a portion of the first linkage structure may pass through the linkage channel(s) so as to enable the intermediate actuation structure to move without interference from the first linkage structure. The linkage channel(s) preferably are oblong or elliptical, however, other designs/configurations may be appropriate (e.g., rectangular). The intermediate actuation structure may include first and second lateral actuation rails which are substantially parallel to a direction of movement of the intermediate actuation structure, and optionally, at least one actuation beam connecting the first lateral actuation rail to the second lateral actuation rail. The intermediate actuation structure may have a central actuation rail positioned between the first and second lateral actuation rails. A plurality of actuation beams may be utilized to connect the first and second lateral actuation rails to the central actuation rail. In some variations, at least one actuation beam of the plurality of actuation beams perpendicularly interfaces with at least one of the first lateral actuation rail, the second lateral actuation rail, and the central actuation rail. Those various features discussed above in relation to the fifth aspect of the present invention may be incorporated into any of the other aspects of the present invention as well, and in any appropriate manner noted herein.
A sixth aspect of the present invention is embodied in a suspension assembly including a first support structure, a second support structure, and an intermediate actuation structure (at least one of which is preferably formed from polysilicon). The first support structure is generally interconnected with a base (which is generally a silicon wafer or any other appropriate base substrate) of a microelectromechanical system. The second support structure is generally interconnected with the first support structure so that the first support structure is positioned between the second support structure of the suspension assembly and the base of the MEM system. The intermediate actuation structure is preferably interconnected with at least one actuator element (e.g. an electrostatic comb) and is generally operatively interposed between and interconnected with the first support structure and the second support structure of the suspension assembly. In other words, using a xe2x80x9cbottom-to-topxe2x80x9d description, the first support structure is positioned toward the bottom (i.e. near or adjacent the base) of the suspension system, and the second support structure is generally disposed opposite the first support structure toward the top of the suspension system. The intermediate actuation structure is preferably xe2x80x9csandwichedxe2x80x9d between the first and second support structures of the suspension system. In this sixth aspect of the present invention, at least one of the first and second support structures generally includes a longitudinal center support beam having elongate first and second lateral sides. This longitudinal center beam generally has a plurality of arms connected to and extending out from the first and second lateral sides of the center support beam.
Various refinements exist of the features noted in relation to the sixth aspect of the present invention. Further features may also be incorporated in this sixth aspect as well. These refinements and additional features may exist individually or in any combination. For example, at least a portion of the intermediate actuation structure may be displaced by a first distance with regard to the base. In response to at least a portion of the intermediate actuation structure being displaced by the first distance, at least a portion of one or both of the first and second support structures may be displaced by a second distance. In some variations, the first distance that the intermediate actuation structure is displaced by may be at least about 2 times greater than the second distance by which at least a portion of one or both the first and second support structures is displaced. For example, a portion of the intermediate actuation structure may be displaced a distance of about 5.8 microns, which in turn may result in a portion of one or both the first and second support structures being displaced a distance of about 2.9 microns.
In the case of the first support structure of the sixth aspect having a center support beam, the plurality of arms may include first, second, third, and fourth lower support arms that are interconnected with the center support beam and at least first and second lower flex arms that are interconnected with the center support beam. The first and second lower support arms and the first lower flex arm may generally be disposed on the first lateral side of the center support beam. Accordingly, the third and fourth lower support arms and the second lower flex arm may generally be disposed on the second lateral side of the center support beam.
In the case of the first support structure of the sixth aspect having a center support beam, the first, second, third, and fourth lower support arms may include respective first, second, third, and fourth fixed ends generally being remotely disposed from the center support beam. In other words, these first, second, third, and fourth fixed ends of the respective first, second, third, and fourth lower support arms are generally positioned opposite the respective ends of attachment to the center support beam. These first, second, third, and fourth fixed ends may be interconnected with the base.
In the case of the sixth aspect, a plurality of base anchors may connect the first support structure to the base. More-specifically, some variations include a plurality of base anchors connecting the first, second, third, and fourth fixed ends of the respective first, second, third, and fourth lower support arms of the first support structure to the base. In some variations, the base has a voltage reference plane. Accordingly, some variations may exhibit one or more of base anchors positioned on the voltage reference plane.
Referring to variations of the sixth aspect having lower flex arms, the first lower flex arm may generally be positioned between the first and second lower support arms. Similarly, the second lower flex arm may generally be positioned between the third and fourth lower support arms. However, other positions of one or both the first and second lower flex arms may be appropriate. In some variations of the sixth aspect, the first lower flex arm may be substantially aligned with the first and second lower support arms. Likewise, the second lower flex arm may be substantially aligned with the third and fourth lower support arms. An entirety of each of the first and second lower flex arms may be separate from and avoid direct contact with the base. In other words, the first and second lower flex arms may be substantially unimpeded by any interconnection of the first and second lower flex arms to the base. The first and second lower flex arms may include respective first and second free ends that may be remotely disposed from the center support beam. In other words, these free ends of the lower flex arms are generally located opposite the ends that connect to the center support beam. The first and second free ends of respective first and second lower flex arms may be separated from and avoid direct contact with the base. In other words, at least some vertical clearance may exist between the base and the first and second free ends of the respective first and second lower flex arms. Some variations of the sixth aspect may include third and fourth lower flex arms interconnected with the center support beam. These third and fourth lower flex arms may have respective third and fourth free ends that are remotely disposed from the center support beam. The third and fourth free ends of the respective third and fourth lower flex arms may be separated from the base.
In the case of the second support structure of the sixth aspect having a center support beam, the plurality of arms may include first, second, third, and fourth upper support arms interconnected with the center support beam and at least first and second upper flex arms interconnected with the center support beam. The first and second upper support arms and the first upper flex arm are generally disposed on the first lateral side of the center support beam. Accordingly, the third and fourth upper support arms and the second upper flex arm are generally disposed on the second lateral side of the center support beam.
Referring to variations of the sixth aspect having upper flex arms, the first upper flex arm may generally be positioned between the first and second upper support arms. Similarly, the second upper flex arm may generally be positioned between the third and fourth upper support arms. The first upper flex arm may be substantially aligned with the first and second upper support arms. Likewise, the second upper flex arm may be substantially aligned with the third and fourth upper support arms. In some variations, an entirety of each of the first and second upper flex arms may be separated from and avoid direct contact with the base. That is, the first and second upper flex arms may be substantially unimpeded by any interconnection of the first and second upper flex arms to the base. These first and second upper flex arms may include respective first and second free ends that are remotely disposed from the center support beam. These first and second free ends of the respective first and second upper flex arms may be separated from and avoid direct contact with the base. Some variations of the sixth aspect may include third and fourth upper flex arms that are interconnected with the center support beam. These third and fourth upper flex arms may have respective third and fourth free ends that are remotely disposed from the center support beam. These third and fourth free ends may be separated from the base. In other words, at least some vertical clearance may exist between the base and these third and fourth free ends.
In some variations of the sixth aspect, the first, second, third, and fourth upper support arms may include respective first, second, third, and fourth fixed ends that are remotely disposed from the center support beam. In other words, the fixed ends of the upper support arms are positioned opposite the ends of the respective support arms that connect with the center support beam. These first, second, third, and fourth fixed ends of the respective first, second, third, and fourth upper support arms may be interconnected with the first support structure. Some variations of the sixth aspect may include a plurality of support anchors interconnecting first, second, third, and fourth fixed ends of the respective first, second, third, and fourth upper support arms of the second support structure to the first support structure.
In the case of the sixth aspect, the intermediate actuation structure may include a central actuator beam interconnected with a displacement multiplier. Displacement multipliers are described in U.S. Pat. No. 6,175,170 to Kota et al. and issued on Jan. 16, 2001, the entire disclosure of which is incorporated by reference herein. The intermediate actuator structure may include the central actuator beam being interconnected with an elevator assembly for positioning a microstructure. The central actuator beam may be parallel to and vertically spaced from the center support beam. In some variations, the central actuator beam may include one or more laterally extending actuator arms. The actuator element (e.g., an electrostatic comb) may be connected to at least one of these laterally extending actuator arms.
In the case of this sixth aspect, a plurality of actuation connectors may be positioned between and interconnect the first support structure with the intermediate actuation structure. Similarly, a plurality of actuation connectors may be positioned between and interconnect the second support structure with the intermediate actuator structure. In some variations, the actuation connectors may be disposed between the intermediate actuation structure and one or more flex arms of one or both the first and second support structures. In one variation, the actuation connectors may be positioned at the free end(s) of one or more of the respective flex arms.
Some variations of the sixth aspect may exhibit configurations wherein each lateral side of the center support rail includes a plurality of support arms and flex arms oriented in an alternating fashion. Other variations of the sixth aspect may exhibit configurations having two or more flex arms adjacent one another on the same lateral side of the center support beam (i.e., no support arm is positioned between the flex arms). Some variations of the sixth aspect may exhibit configurations wherein the number, size, shape, and orientation of the flex and support arms positioned on the first lateral side of the center support beam are a mirror image of the number, size, shape, and orientation of the flex and support arms positioned on the second lateral side of the center support beam. However, other variations of the sixth aspect may exhibit configurations wherein one or more of the number, size, shape, and orientation of one or both the flex and support arms positioned on the first lateral side of the center support beam may differ from one or more of the number, size, shape, and orientation of one or both the flex and support arms positioned on the second lateral side of the center support beam.
At least portions of the second support structure, in the case of the sixth aspect, may be substantially parallel to and vertically spaced from the first support structure. Some variations of the sixth aspect may exhibit only one of the first and second support structures having first and second center support rails, which may be substantially parallel to and vertically spaced from the center support beam. In such variations, the first center support rail may be laterally spaced from and substantially parallel to the second center support rail. The sixth aspect may also include some variations wherein each of the first and second support structures includes a center support beam. Some variations may exhibit both the first and second support structures having respective first and second pluralities of arms. In such variations, the first plurality of arms may be vertically spaced from and substantially parallel to the second plurality of arms. Regardless, one or more of the intermediate actuation structure and the first and second support structures, if the suspension assembly may be made from a structural material having a tensile strength of at least about 0.25 GPa. Those various features discussed above in relation to the sixth aspect of the present invention may be incorporated in any other aspects of the present invention, and in any appropriate manner noted herein.
A seventh aspect of the present invention is embodied in a suspension assembly for at least assisting in supporting a first actuation element of a microelectromechanical system and allowing movement of the first actuation element of a microelectromechanical system relative to a base substrate. The suspension assembly of this seventh aspect generally includes a longitudinal support beam having elongate first and second lateral sides and a plurality of first lateral beams extending out from the first and second lateral sides of the support beam. In addition, at least one of the first lateral beams of this seventh aspect is generally anchored to the base substrate. In other words, at least a portion of one of these first lateral beams is generally substantially immobilized by some attachment to the substrate.
Various refinements exist of the features noted in relation to the seventh aspect of the present invention. Further features may also be incorporated in this seventh aspect as well. These refinements and additional features may exist individually or in any combination. For example, the first lateral beams may be oriented in a substantially perpendicular relationship with respect to the support beam. At least one of the first lateral beams may include a fixed end disposed most remote from the support beam. This fixed end may be anchored to the base substrate. In some variations, ones of the first lateral beams may be vertically spaced from and devoid of any anchoring to the base substrate. In other words, a lower surface(s) (i.e., the surface of the respective first lateral beam which faces the base substrate) of the first lateral beam(s) is generally free from any attaching means which would interconnect the lower surface of the first lateral beam to the base substrate.
In the case of the seventh aspect, the plurality of first lateral beams may be anchored to the base substrate. Each of these first lateral beams may include a fixed end that is disposed most remote from the support beam (i.e., opposite from the end that attaches to the support beam) and that is generally anchored to the base substrate. Some variations of this seventh aspect may include a plurality of second lateral beams. The second lateral beams may be oriented in a substantially perpendicular relationship with respect to the support beam. The second lateral beams may be oriented in a substantially parallel relationship with respect to the first lateral beams. However, other orientations of the second lateral beams may be appropriate. Each of the second lateral beams may include a free end that may be vertically spaced from and devoid of any anchoring to the base substrate.
Some variations of this seventh aspect may include an actuation assembly. The actuation assembly of this seventh aspect may have a plurality of actuation beams oriented substantially parallel to the support beam and interconnected with ones of the plurality of the first lateral beams. This actuation assembly may be vertically displaced from the support beam. In some variations, the first actuation element may be interconnected to at least one of the actuation beams. Some variations may exhibit the actuation assembly having a plurality of third lateral beams oriented substantially perpendicular to the plurality of the actuation beams and extending between and interconnecting at least ones of the plurality of the actuation beams. In such variations, the first, actuation element may be interconnected to at least one of the plurality of third lateral beams.
A suspension assembly of this seventh aspect may include a support assembly generally having a first central beam, a second central beam adjacent to the first central beam, and a plurality of fourth and fifth lateral beams extending out from the first and second central beams. In some variations, one or both the plurality of third lateral beams and the plurality of fourth lateral beams may be interconnected with the plurality of first lateral beams. The plurality of actuation beams of the actuation assembly may be disposed between and interconnected with the plurality of first lateral beams and the plurality of fifth lateral beams. Those various features discussed above in relation to any of the aspects of the present invention may be incorporated in any other aspects of the present invention, and in any appropriate manner noted herein.